title: [High prevalence without reactivation of herpes virus 6 in subjects with chronic fatigue syndrome].
abstract: BACKGROUND
  Chronic fatigue syndrome (CFS) is a disorder of unknown etiology. Some viruses have been associated with CFS etiology, specially herpesviruses, enteroviruses and retroviruses. Some studies suggest an association between human herpesvirus-6 (HHV-6) and CFS. In order to know if there is an active HHV-6 infection in CFS patients we studied the immunologic and virologic status of HHV-6.
  
  
  METHODS
  Twenty patients with CFS were studied. IgG and IgM anti HHV-6 were determined by indirect immunofluorescence assay. DNA from serum and peripheral blood mononuclear cells (PBMC) were studied by dot- and Southern-blotting and nested-PCR to detect HHV-6 DNA. HHV-6 RNA from PBMC were amplified by RT(retrotranscription)-PCR.
  
  
  RESULTS
  Ten patients (50%) had IgG anti-HHV-6 in serum but none had IgM anti-HHV-6. Dot-blotting of DNA from 200 microliters of serum and Southern-blotting of 10 micrograms of PBMC DNA were negative. Nested-PCR from sera were negative. Nested-PCR with 1 microgram PBMC DNA were positive in 8 out 20 (40%) and with 5 micrograms PBMC DNA were positive in 16 out of 20 (80%). No viral RNA were detected in PBMC.
  
  
  CONCLUSIONS
  There is a high proportion of CFS patients infected with HHV-6 but with low viral load. Results do not support HHV-6 reactivation in CFS patients.
authors.affiliation: Laboratorio de Biología Molecular, Hospital Provincial San Telmo, Palencia.
authors.forename: J I
authors.initials: JI
authors.lastname: Cuende
authors.forename: P
authors.initials: P
authors.lastname: Civeira
authors.forename: N
authors.initials: N
authors.lastname: Diez
authors.forename: J
authors.initials: J
authors.lastname: Prieto
mesh_terms: D000328:Adult; D015673:Fatigue Syndrome, Chronic / Q000097:blood / Q000821:virology*; D005260:Female; D015654:Herpesvirus 6, Human / Q000276:immunology / Q000302:isolation & purification* / Q000502:physiology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D008875:Middle Aged; D015995:Prevalence
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M
vernacular_title: Alta prevalencia sin reactivación del herpesvirus humano-6 en sujetos con síndrome de fatiga crónica.